alert

adjective
\ ə-ˈlərt How to pronounce alert (audio) \

Definition of alert

 (Entry 1 of 3)

1a : watchful and prompt to meet danger or emergency an alert guard trying to stay alert to possible problems
b : quick to perceive and act mentally alert
2 : active, brisk elicited an alert response

alert

noun

Definition of alert (Entry 2 of 3)

1 : a state of careful watching and readiness especially for danger or opportunity on 24-hour alert
2a : an alarm or other signal of danger traffic alerts They sounded the alert.
b : an urgent notice … an alert to parents … about new immunization requirements.— Ann Schrader
3 : the period during which an alert is in effect
on the alert
: looking for or expecting something (such as danger or an opportunity) Drivers need to be on the alert for icy condition. always on the alert for a good bargain

alert

verb
alerted; alerting; alerts

Definition of alert (Entry 3 of 3)

transitive verb

1 : to call (someone) to a state of readiness : warn alerted the school board of a possible teachers' strike alert the authorities
2 : to make (someone) aware of something alerted the public to the dangers of pesticides

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Other Words from alert

Adjective

alertly adverb
alertness noun

Synonyms & Antonyms for alert

Synonyms: Adjective

Synonyms: Noun

Synonyms: Verb

Antonyms: Adjective

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Choose the Right Synonym for alert

Adjective

watchful, vigilant, wide-awake, alert mean being on the lookout especially for danger or opportunity. watchful is the least explicit term. the watchful eye of the department supervisor vigilant suggests intense, unremitting, wary watchfulness. eternally vigilant in the safeguarding of democracy wide-awake applies to watchfulness for opportunities and developments more often than dangers. wide-awake companies latched onto the new technology alert stresses readiness or promptness in meeting danger or in seizing opportunity. alert traders anticipated the stock market's slide

intelligent, clever, alert, quick-witted mean mentally keen or quick. intelligent stresses success in coping with new situations and solving problems. an intelligent person could assemble it fast clever implies native ability or aptness and sometimes suggests a lack of more substantial qualities. clever with words alert stresses quickness in perceiving and understanding. alert to new technology quick-witted implies promptness in finding answers in debate or in devising expedients in moments of danger or challenge. no match for his quick-witted opponent

Examples of alert in a Sentence

Adjective An alert guard stopped the robbers. He was tired and had trouble staying alert while he was driving. She wasn't mentally alert enough to answer the questions. An alert watchdog guarded the door. Noun They sounded an alert when enemy planes were approaching the city. Medical officials have put out an alert to hospitals to look out for the virus. The government has issued a terrorism alert. Verb Several neighbors alerted the authorities when they noticed strangers acting suspiciously. The governor alerted island residents that a hurricane was coming. The teacher alerted the students that tests would be given the next day.
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Recent Examples on the Web: Adjective GebreMariam is currently weighing whether to accept more of the models from Boeing, which has revamped the aircraft with new software and alert systems. Aric Jenkins, Fortune, "‘We Won’t Be the First:’ Ethiopian Airlines CEO Weighs Reintroducing 737s After Fatal Boeing Crash," 19 Nov. 2019 The investigators found that an alert vehicle operator would have had two to four seconds to detect and avoid pedestrian Elaine Herzberg, who was crossing a street when struck by Uber's self-driving vehicle. Matt Mcfarland, CNN, "Feds blame distracted test driver in Uber self-driving car death," 19 Nov. 2019 The Indiana Department of Transportation urges motorists to be alert on the roads and slow down in construction zones. Kellie Hwang, Indianapolis Star, "These are the construction projects happening on Indianapolis interstates this weekend," 1 Nov. 2019 The city asks drivers to be alert to street closures, lane changes, detours, and delays. oregonlive.com, "Portland metro Wednesday traffic: Paving work closes streets in Vancouver," 21 Aug. 2019 Call these two winning ensembles corporate girl gone wild—somebody alert HR! Christian Allaire, Vogue, "Nobody Subverts the Suit Like Kristen Stewart," 6 Nov. 2019 One boy, who is about 12, hiked several miles to La Mora to alert family members about what had happened, said David Langford, a relative. Elisabeth Malkin, New York Times, "Mormon Family Massacre Stuns Mexico, Laying Bare Government’s Helplessness," 6 Nov. 2019 Roslyn, or Roz for short, is Bernadin's service animal and medical alert dog, police said. Fox News, "Texas police ask public for help after veteran's service dog stolen," 3 Nov. 2019 The Clemson team said Twitter's more open APIs allowed them to identify suspected Russian trolls and alert Twitter. Elizabeth Cohen, CNN, "She was called the n-word and given instructions to slit her wrists. What did Facebook do?," 1 Nov. 2019 Recent Examples on the Web: Noun High winds and low humidity have fire officials on alert as power shut-offs sweep across the North Bay, but the red flag warnings issued throughout the region could give way to rainfall early next week. Michael Cabanatuan, SFChronicle.com, "Rain could save Bay Area from extreme fire weather starting next week," 20 Nov. 2019 Many will be on alert for another Asian joke from Yang, as his representation of Asian Americans remains a source of division within the community. NBC News, "Is Andrew Yang 'reclaiming' stereotypes with Asian jokes? Experts say not so much.," 20 Nov. 2019 Users should also be on the alert for spear phishing and other forms of attack that make use of their personal information. Dan Goodin, Ars Technica, "Password data for ~2.2 million users of currency and gaming sites dumped online," 19 Nov. 2019 Ironically, our community never intended to corner the market on staying socially alert. Essence, "The OverExplainer: Young, Woke and Tired," 15 Nov. 2019 On Friday, the U.S. government increased its security alert to prohibit personnel from traveling to the city of Chihuahua, capital of the state of the same name, some 235 miles south of El Paso. David Agren, azcentral, "Mexico invites U.S. to join investigation of ambush that killed mothers and children," 10 Nov. 2019 The location of tactical nuclear weapons in aircraft shelters is part of the Cold War legacy, when airplanes remained on alert to drop tactical nukes on any Soviet hordes advancing along its southern flank. Joe Pappalardo, Popular Mechanics, "Could Someone Actually Steal a U.S. Nuke?," 25 Oct. 2019 The league is changing and toughening its code of conduct for fans, especially putting those in closest proximity to the players and the court on alert that anything over the line will lead to ejections and possibly more. Tim Reynolds, chicagotribune.com, "Addressing growing fan behavior problem top priority for NBA," 22 Oct. 2019 France remains on alert after a string of deadly Islamic State attacks in 2015 and 2016 that heightened the country’s security posture at home and abroad. San Diego Union-Tribune, "France: Person arrested in Sept. 11-style attack threat," 18 Oct. 2019 Recent Examples on the Web: Verb Minutes after the attack, Mr. Hershkowitz said a person came into the synagogue to alert them about the man on the ground, which prompted him to call 911. Azi Paybarah, New York Times, "Man Is Stabbed and Slashed Steps Away From a Synagogue in New York," 20 Nov. 2019 His big mistake was copying staffers of two senators who controlled his nomination, Kentucky's Rand Paul and Idaho's Jim Risch, alerting them to his willingness to donate more after confirmation. CBS News, "Possible pay-to-play scheme for ambassador role in Trump administration uncovered by CBS News," 18 Nov. 2019 Steve Bannon, who served as the campaign’s chief executive, testified during the trial the trial that Stone had boasted about his ties to WikiLeaks and its founder Julian Assange, alerting them to pending new batches of damaging emails. Ashraf Khalil, Twin Cities, "Roger Stone guilty of witness tampering, lying to Congress," 15 Nov. 2019 Steve Bannon, who served as the campaign’s chief executive, testified during the trial the trial that Stone had boasted about his ties to WikiLeaks and its founder Julian Assange, alerting them to pending new batches of damaging emails. Anchorage Daily News, "Roger Stone found guilty of witness tampering and lying to Congress in case related to WikiLeaks," 15 Nov. 2019 Steve Bannon, who served as the campaign’s chief executive, testified that Stone had boasted about his ties to WikiLeaks and its founder Julian Assange, alerting them to pending new batches of damaging emails. NBC News, "Closing arguments underway in Roger Stone trial," 13 Nov. 2019 Difficulty urinating An epidural will numb the nerves that alert you when your bladder is full, Dr. Greves says. Samantha Lauriello, Health.com, "Epidural Side Effects and Risks, According to an Ob-Gyn," 12 Nov. 2019 Stop and absorb, but don’t expect a red-and-green theme to alert you. Dewayne Bevil, orlandosentinel.com, "New holiday look at Disney’s Animal Kingdom: What we saw on the first day," 9 Nov. 2019 Bloomberg himself has called prominent Democrats to alert them to his likely run, and his staff is scrambling to meet fast-approaching primary filing deadlines. Thomas Beaumont, The Denver Post, "Michael Bloomberg to pass on Iowa, New Hampshire, focus on Super Tuesday states in possible presidential bid," 8 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alert.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of alert

Adjective

1618, in the meaning defined at sense 1a

Noun

1801, in the meaning defined at sense 1

Verb

circa 1868, in the meaning defined at sense 1

History and Etymology for alert

Adjective

borrowed from French alerte, going back to Middle French a l'herte "on guard, on the watch," borrowed from Italian all'erta, originally in the collocation stare all'erta "to be on the watch," literally, "to be on the height" (with erta "height, hill, steep ascent," noun derivative from feminine of erto, past participle of ergere "to raise, elevate," going back to Vulgar Latin *ērgere, by syncope from Latin ērigere) — more at erect entry 1

Note: The earliest citation for the word in the Oxford English Dictionary suggests direct borrowing from Italian, or at least recognition of an Italian source: "In this place the Prince [of Orange] finding his rutters [cavalry soldiers] alert, (as the Italians say) with aduise of his valiant brother, hee sent his Trumpets to D. d' Alua…." (Sir Roger Williams, The Actions of the Lowe Countries, London, 1618, p. 27).

Noun

noun derivative of alert entry 1 (or borrowed from French alerte, derivative of alerte, adjective)

Verb

verbal derivative of alert entry 1 or alert entry 2

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Time Traveler for alert

Time Traveler

The first known use of alert was in 1618

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Statistics for alert

Last Updated

26 Nov 2019

Cite this Entry

“Alert.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/alerts. Accessed 5 December 2019.

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More Definitions for alert

alert

adjective
How to pronounce alert (audio)

English Language Learners Definition of alert

 (Entry 1 of 3)

: able to think clearly and to notice things

alert

noun

English Language Learners Definition of alert (Entry 2 of 3)

: something (such as a message or loud sound) that tells people there is some danger or problem : an alarm or signal of danger
: the state of being ready for something you have been warned about (such as an attack)

alert

verb

English Language Learners Definition of alert (Entry 3 of 3)

: to give (someone) important information about a possible problem, danger, etc. : to warn (someone)
: to make (someone) aware of something

alert

adjective
\ ə-ˈlərt How to pronounce alert (audio) \

Kids Definition of alert

 (Entry 1 of 3)

1 : watchful and ready especially to meet danger But he was alert at night, too, on the road, always listening intently …— Lois Lowry, The Giver
2 : quick to understand and act An alert reader noticed the error in grammar.

Other Words from alert

alertly adverb The prairie dog sat alertly beside the opening of its burrow.

alert

noun

Kids Definition of alert (Entry 2 of 3)

1 : an alarm or signal of danger The police issued an alert.
2 : the period during which an alert is in effect We stayed indoors during the alert.
on the alert
: watchful against danger … the remark had set us all on the alert, straining ears and eyes …— Robert Louis Stevenson, Treasure Island

alert

verb
alerted; alerting

Kids Definition of alert (Entry 3 of 3)

: to make aware of a need to get ready or take action : warn The siren alerted us that a tornado was approaching.

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More from Merriam-Webster on alert

Thesaurus: All synonyms and antonyms for alert

Rhyming Dictionary: Words that rhyme with alert

Spanish Central: Translation of alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

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